Cai_Chapter 6 - FIGURE 6-3 Reaction coordinate diagram...

FIGURE 6-3 Reaction coordinate diagram comparing enzyme-catalyzed and uncatalyzed reactions.In the reaction S → P, the ES and EP intermediates occupy minima in the energy progress curve of the enzyme-catalyzed reaction. The terms ΔG‡uncatand ΔG‡catcorrespond to the activation energy for the uncatalyzed reaction and the overall activation energy for the catalyzed reaction, respectively. The activation energy is lower when the enzyme catalyzes the reaction.

This preview
has intentionally blurred sections.
Sign up to view the full version.

FIGURE 6-8 (part 1) How a catalyst circumvents unfavorable charge development during cleavage of an amide.The hydrolysis of an amide bond, shown here, is the same reaction as that catalyzed by chymotrypsin and other proteases. Charge development is unfavorable and can be circumvented by donation of a proton by H3O+(specific acid catalysis) or HA (general acid catalysis), where HA represents any acid. Similarly, charge can be neutralized by proton abstraction by OH–(specific base catalysis) or B: (general base catalysis), where B: represents any base.

FIGURE 6-8 (part 2) How a catalyst circumvents unfavorable charge development during cleavage of an amide.The hydrolysis of an amide bond, shown here, is the same reaction as that catalyzed by chymotrypsin and other proteases. Charge development is unfavorable and can be circumvented by donation of a proton by H3O+(specific acid catalysis) or HA (general acid catalysis), where HA represents any acid. Similarly, charge can be neutralized by proton abstraction by OH–(specific base catalysis) or B: (general base catalysis), where B: represents any base.

This preview
has intentionally blurred sections.
Sign up to view the full version.

FIGURE 6-8 (part 3) How a catalyst circumvents unfavorable charge development during cleavage of an amide.The hydrolysis of an amide bond, shown here, is the same reaction as that catalyzed by chymotrypsin and other proteases. Charge development is unfavorable and can be circumvented by donation of a proton by H3O+(specific acid catalysis) or HA (general acid catalysis), where HA represents any acid. Similarly, charge can be neutralized by proton abstraction by OH–(specific base catalysis) or B: (general base catalysis), where B: represents any base.

FIGURE 6-9 Amino acids in general acid-base catalysis.Many organic reactions are promoted by proton donors (general acids) or proton acceptors (general bases). The active sites of some enzymes contain amino acid functional groups, such as those shown here, that can participate in the catalytic process as proton donors or proton acceptors.

This preview
has intentionally blurred sections.
Sign up to view the full version.

What students are saying

As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran
Temple University Fox School of Business ‘17, Course Hero Intern

I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana
University of Pennsylvania ‘17, Course Hero Intern

The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.